Technical Field
The present disclosure relates to a backlight unit and a liquid crystal display device including the same.
Description of the Related Art
As an information-oriented society has developed, a variety of needs with respect to a display device for displaying an image have increased. Accordingly, recently, several flat panel display devices, such as a liquid crystal display (LCD) device, a plasma display panel (PDP), an organic electroluminescence display device, have been utilized. Among flat panel display devices, an LCD device displays an image by modulating light which is incident from a backlight unit, by controlling an electric field applied to a liquid crystal layer.
Backlight units of such LCDs may be classified into a direct light type backlight unit and an edge light type backlight unit depending on an arrangement of light sources. In a direct light type backlight unit, a plurality of light sources are arranged on a rear surface of an LCD panel and light emitted by the light sources is transmitted toward the LCD panel. On the other hand, in the edge light type backlight unit, a plurality of light sources are arranged on one side of a bottom of an LCD panel and light emitted by the light sources is transmitted toward the LCD panel by using a light guide plate.
For the light sources of the direct light type or edge light type backlight unit, white light, in which blue light, red light, and green light are mixed, is emitted toward the rear surface of the LCD panel or a side of the light guide plate. Here, the green light is generated by absorbing, by a green fluorescent material, the blue light, and the red light is generated by absorbing, by a red fluorescent material, the blue light.
Referring to FIG. 1, it may be seen that a part of a green light emitting area overlaps a red color absorption area. Due to such properties, since the red fluorescent material absorbs the green light as much as an area R in which the green light emitting area overlaps the red color absorption area, the green light is reduced. Accordingly, luminance of light is reduced.